Tomei said she visited Clooney's Lake Como home a few weeks ago while she and other cast members were promoting The Ides of March at Italy's Venice Film Festival.

Tomei said Clooney offered a skinny dipping challenge that she accepted along with Evan Rachel Wood and talk show host Charlie Rose, who plays himself in the movie. "So he throws the gauntlet down: 'Are you guys gonna jump in the lake?'" She then reveals: "We wound up all skinny dipping, let's just cut to the chase."

O'Brien then joked about possibly being invited himself to a future romp with Clooney. "If George Clooney invites me to his Lake Como palazzo, I will walk around naked the entire time." To this, Tomei responds: "You're gonna get an invite, like tomorrow, and you're gonna have to live up to that, I'm sure."